The present invention pertains to decorative light strings comprising a plurality of electrically connected incandescent lamps and, more particularly, to a blank used as a replacement for a lamp in such a string where no light is desired.
Strings of decorative lights comprising individual interconnected incandescent lamps are well known in the art. For example, the typical Christmas tree light string may include as many as 50 or more individual lamps including lamp holders which are wired to allow successive strings to be connected in series. Series connection of multiple light strings facilitates the use of such strings to decorate a Christmas tree, but such connections are also useful when utilizing such light strings for other decorative purposes, such as decorating the outside of a house or creating a lighted decorative message. When utilizing interconnected light strings for such other decorative purposes, portions of one or more of the interconnected strings may span regions where it would be desirable not to have lighted lamps. For example, the spaces between windows encircled with lights or the spaces between the words in a lighted message may preferably be left unlighted.
It is known to wire Christmas tree light strings in series and to use shunt-type incandescent lamps in those strings so that, if the filament of a lamp burns out, a series connection in the string is nonetheless maintained and the remaining lamps in the string remain lit. The present invention provides a replacement blank for such an incandescent lamp for use in those regions of the string where no light or lights are desired.